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<head>
    <meta charset="utf-8">
    <title>选择标题=一个特定值的元素(使用（|）分隔属性和值)</title>
    <style>
        [lang|=en] {
            color: blue;
        }
    </style>
</head>

<body>
    <h2>将适用:</h2>
    <p lang="en">Hello!</p>
    <p lang="en-us">Hi!</p>
    <p lang="en-gb">Ello!</p>
    <hr>
    <h2>将不适用:</h2>
    <p lang="us">Hi!</p>
    <p lang="no">Hei!</p>
</body>

</html>